Dots and Boxes is a pencil-and-paper classic: two players take turns joining dots, and whoever closes a box claims it. It looks simple, but the endgame rewards real planning. Here is how to play against the computer and how to beat it.
The rules
On your turn, draw one line between two neighboring dots, across or down.
If your line completes the fourth side of a box, you claim it and must draw again. One line can close two boxes at once.
If your line closes nothing, the turn passes to the other player.
When every box is claimed, the player with more boxes wins. On a 4×4 board an 8–8 draw is possible.
Playing on Everyday Games
Tap between two dots to draw a line. Faint dashes show the lines still open. Your lines and boxes are blue and the computer’s are coral, and the outlined score shows whose turn it is.
Choose a 3×3, 4×4 or 5×5 board and an Easy, Normal or Hard opponent from New game. Who starts alternates each game. Undo takes back your last line and the computer’s reply, and a game in progress is saved so you can come back to it.
Early game: don’t draw the third side
A box with three sides drawn is a gift to whoever moves next. Early on, play lines that don’t give a box a third side. These safe lines run out as the board fills up, and that is when the real game starts.
Chains and the long-chain rule
When no safe lines are left, the open boxes form chains (rows of boxes joined end to end) and loops. Any line you draw now hands boxes to your opponent.
Give away the shortest chain you can. Open a two-box chain with the line between the two boxes, so it can’t be handed back.
Long chains (three or more boxes) decide the game. The player who isn’t forced to open the first long chain usually wins most of the boxes. Count the safe lines left to see who that will be, and try to make it you.
Double-dealing: keeping control
When you are handed a long chain, you don’t have to take it all. Take every box except the last two, then draw the far end of the chain instead of the line between those two boxes. Your opponent gets two boxes, but must then open the next chain for you. Giving up two boxes each time to keep control is how strong players win. In a loop, leave the last four boxes instead.
On Hard, the computer does exactly this, and it calculates the endgame exactly once the chains take shape. Easy grabs boxes but often gives them away, and Normal plays safe lines and takes whole chains but never double-deals.